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CLASSIFICATION  OF  STRUCTURAL  STEELS.                  4:01
ties, for the derailment of a train will subject certain members to great deformation; such an accident is a possibility which human foresight seems powerless to avoid, but carelessness in the shop stands on a different footing, for it is caused by positive and unnecessary acts in error.
The quench-test depends upon slight differences in the methods of heating and cooling, differences almost imperceptible and unex-plainable, and the same steel may be made to pass or fail under modes of treatment which seem inherently identical. It would appear, therefore, that no warrant exists for the imposition of this test upon material for a railroad bridge, which is not calculated to withstand a conflagration followed by a flood. This position is being taken by a large number of engineers, and a quench-test is rapidly becoming a thing of the past.
SEC. XYIIIg.—Standard specifications.—The first successful effort in America to standardize specifications for iron and steel was made in August, 1895, by the Association of American Steel Manufacturers. The formation of the American Section of the International Association for Testing Materials on June 16, 1898, was the next important move in this direction, but the work of both organizations has been superseded by the formation of The American Society for Testing Materials. This is an offshoot of the International Society, and its creation was made advisable by two conditions:
(1)   The American members deem of first importance the construction of a uniform set of specifications for the use of buyer and seller, while the foreign members wish to discuss the refinements in methods of testing, postponing to the future the construction of a set of specifications.
(2)   The results thus far obtained in America toward making working specifications render it very desirable that the work be pursued under some definite organization, representing engineers, manufacturers, inspectors and investigators.
The society was definitely organized at Atlantic City on June 12, 1902, and elected as its secretary, Prof. Edgar Marburg, of the University of Pennsylvania, Philadelphia, Pa. It publishes for general circulation its standard specifications on steel, and is trying to harmonize by open discussion at its meetings the conflicting views held by different engineering societies and committees.